Inflatable member for an endoscope sheath

ABSTRACT

Apparatus and methods for attaching and forming enclosed inflatable members on an endoscope assembly with a disposable sheath are disclosed. In one embodiment, an apparatus includes a flexible and resilient cuff member that is positioned on the outer surface of the disposable sheath and sealably and fixedly bonded to the sheath cover material at the cuff edges to form an annular space capable of being inflated. The inflatable member formed thereby is inflated through a lumen internal to the sheath that has an opening into the interior annular space. The inflatable member may be inflated to exert a longitudinal force on the insertion tube, thereby moving the endoscope assembly along a body passage. Alternately, a sheath may include a plurality of inflatable cuffs that may be inflated to create an isolated space therebetween within the body passage.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is a continuation-in-part of pending U.S. patentapplication Ser. No. 09/702,155, filed Oct. 30, 2000.

TECHNICAL FIELD

[0002] This invention relates generally to endoscopy, and moreparticularly to inflatable members attached to an endoscopic instrument.

BACKGROUND OF THE INVENTION

[0003] The use of endoscopes for diagnostic and therapeutic purposes iswidespread. For example, there are upper endoscopes for examination ofthe esophagus, stomach and duodenum, colonoscopes for the examination ofthe colon, angioscopes for vascular examination, bronchoscopes forexamining the bronchi, laparoscopes for examining the peritoneal cavity,and arthroscopes for the examination of joint spaces. The followingdiscussion applies to all of these types of endoscopes.

[0004] An endoscope for examining the bronchial tract and conductingtransbronchial biopsies is a good example of the usefulness ofendoscopic technology. These devices, known as flexible bronchoscopes,are widely used in diagnosing pulmonary diseases since they are capableof reaching the more distal bronchi in the bronchial tract. To properlynavigate and view a bronchial area, the bronchoscope is generallystructured to contain a fiber optic bundle within the elongated probesection. Alternatively, the bronchoscope may utilize other means to viewthe bronchial area, such as a video device positioned within thebronchoscope. In addition to providing a direct viewing capability,flexible bronchoscopes generally possess a means to remove tissuesamples, or other material from the bronchial tract for biopsy orculture purposes. Tissue samples for biopsy purposes may be collectedusing a biopsy forceps extending from the distal end of the bronchoscopeor by brushing the suspect area to capture cellular material forsubsequent microscopic examination. Another commonly used technique tocollect cellular material is to wash, or lavage, the suspect area. Whena lavage procedure is used, a solution is injected into the bronchialpassage and subsequently withdrawn by suction through the distal end ofthe broncoscope to capture cellular material. Following withdrawal ofthe lavage fluid, the cellular material may be subjected to acytological examination or culture.

[0005] One difficulty encountered in the use of endoscopes iscontinuously maintaining the endoscopic probe in a selected locationwithin a body passage during the examination. Movement of the endoscopicprobe while it is positioned within a body passage may occur for anumber of reasons. For example, movement of the endoscope may occur dueto an unintended bodily movement of the operator while the patient isundergoing the examination, or by an involuntary movement of the patientin response to the examination. Once the distal end of the endoscope hasbeen dislodged from its intended location, it must be carefullyrepositioned before the examination may be resumed. Movement of theendoscope within a body passage is particularly pronounced duringbronchoscopic examinations, since the patient must continue to breatheduring the examination. Further, involuntary bronchospasmodic eventswithin the bronchial passages may occur during the examination that willdisrupt the location of the distal end of the bronchoscope. Asignificant additional difficulty resulting from unintended patientmovement may arise when a biopsy procedure is conducted. Since a biopsyforceps or brush is generally used, an uncontrolled or unintendedcutting of tissue in the passage due to patient movement may lead tohemoptysis. Moreover, since the biopsy forceps, or brush may reach andperforate the pleura, pneumothorax may also occur.

[0006] Still another difficulty encountered in the use of endoscopes fordiagnostic purposes is the inability to sealably isolate a portion ofthe endoscope from the remainder of the body passage during anendoscopic examination. To facilitate internal viewing of a passage, forexample, the fluid occupying the cavity is generally removed by means ofa suction channel in the endoscope, which may be followed by theintroduction of a gas through an additional channel in the endoscope todistend the internal space. Other endoscopic applications may requirethat a fluid be retained within the portion of the body passage that hasbeen sealably isolated. For example, in transbronchial diagnosticprocedures such as bronchoalveolar lavage, the bronchoscope is used togently irrigate the air spaces in a distal air passage with a solution.Isolation of the solution to the region surrounding the distal end ofthe bronchoscope is required so that cellular samples removed during thelavage are sufficiently localized to be of diagnostic value. Inparticular, when collecting samples by lavage for use in the diagnosisof infectious pulmonary diseases, the sample must not be contaminated bybacterial or other agents transported to the distal end of the probe bythe unrestrained movement of the solution through the passage.

[0007] Yet another difficulty encountered in the use of endoscopesoccurs when the endoscope must be positioned at a relatively deeplocation within a body passage, so that a relatively long portion of theendoscope must be inserted into the patient. In such cases, theendoscope may be resistant to small, or incremental movements within thepassage. Moreover, in certain cases, the endoscope length may developsufficient resistance to further inward movement, so that the endoscopeis prevented from extending to the intended location. Similardifficulties may also occur when the passage is relatively short, butincludes relatively highly curved segments. Since the operator isgenerally limited to positional manipulations of exposed portions of theendoscope, considerable difficulty may be encountered in properlypositioning the endoscope within body passages under these conditions.

[0008] Increasingly, endoscopes are used with disposable sheaths thatare positioned over the insertion tube of the endoscope to avoid thecommunication of disease from one patient to another. An additionaladvantage of the disposable sheath is that it allows the device to beused at more frequent intervals, since the need for lengthy cleaning andsterilization procedures is largely eliminated. Generally, the sheath iscomprised of a flexible, thin, resilient material, such as latex, orother similar materials, that fits over and surrounds the insertion tubeof the endoscope so the insertion tube is completely isolated fromcontaminants. The sheath is generally further comprised of a viewingwindow at the distal end, and may include a plurality of internalchannels, or lumens, through which biopsy samples or fluids may beeither introduced or removed. Accordingly, an additional difficultyencountered in the use of endoscopes concerns the incorporation ofpositioning and passage-blocking means into the disposable outer sheath.

[0009] Consequently, there exists a need in the art for an apparatusthat will continuously maintain an endoscopic probe in a selectedposition within a body passage during the examination. In addition, theapparatus must be able to sealably close the passage to either retainfluids within a closed space, or to prevent a fluid from reoccupying thespace during an examination. Further, there exists a need in the art foran apparatus that permits an endoscopic probe to be properly positionedwithin a long body passage, and/or where the passage is highly curved.Finally, the apparatus must be compatible with disposable sheaths usedwith endoscopes.

SUMMARY OF THE INVENTION

[0010] The invention is directed towards apparatus and methods forattaching and forming enclosed inflatable members on an endoscopeassembly with a disposable sheath. In one aspect, an apparatus inaccordance with the invention includes a flexible and resilient cuffmember that is positioned on the outer surface of the disposable sheathand sealably and fixedly bonded to the sheath cover material at the cuffedges to form an annular space capable of inflation. The inflatablemember formed thereby is inflated through a lumen internal to the sheaththat has an opening into the interior annular space. In another aspect,the annular space may be divided into separate inflatable lobes. Instill another aspect, the cuff member is a flexible and resilientenclosed member that is substantially toroidal in shape that ispositioned on the outer surface of the sheath. In a further aspect, theinflatable member is formed from an excess length of sheath covermaterial disposed on the disposable sheath. A single reentrant fold ofsheath material is formed with an edge that is sealably and fixedlybonded to the sheath cover material to form an annular space capable ofinflation. In still another aspect, the excess length of cover materialmay be used to form members with dual reentrant folds that compriseinflatable members with single and dual inflatable lobes. In anotheraspect, at least a pair of enclosed inflatable members are spaced apartalong the sheath of an endoscope insertion tube, which has a pluralityof openings that project through the sheath to communicate a fluid tothe space formed between the inflatable members. In still anotheraspect, at least a single enclosed inflatable member that has a firstportion capable of a first expansion when inflated, and a second portioncapable of a second expansion when inflated, is positioned on anendoscope sheath of an insertion tube to assist in the movement of theendoscope along a body passage.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a partial cross-sectional view of an endoscope assemblywith an inflatable cuff according to an embodiment of the invention.

[0012]FIG. 2 is a cross-sectional view of an inflatable cuff accordingto another embodiment of the invention.

[0013]FIG. 3 is a cross-sectional view of an inflatable cuff accordingto still another embodiment of the invention.

[0014]FIG. 4 is a cross-sectional view of an inflatable cuff accordingto yet another embodiment of the invention.

[0015]FIG. 5 is a cross-sectional view of an inflatable cuff accordingto another alternative embodiment of the invention.

[0016]FIG. 6 is a cross-sectional view of an inflatable cuff accordingto still another alternative embodiment of the invention.

[0017]FIG. 7 is a cross-sectional view of an endoscope assembly withinflatable cuffs according to another embodiment of the invention.

[0018]FIG. 8 is a cross-sectional view of an endoscope assembly withinflatable cuffs according to still another embodiment of the invention.

[0019]FIG. 9 is a cross-sectional view of an endoscope assembly withinflatable cuffs according to still another embodiment of the invention.

[0020]FIG. 10 is a cross-sectional view of an endoscope assembly withinflatable cuffs according to still another embodiment of the invention.

[0021]FIG. 11 is an isometric view of an endoscope assembly withinflatable cuffs according to yet another embodiment of the invention.

[0022]FIG. 12 is a partial side view of an endoscope assembly withinflatable cuffs according to still yet another embodiment of theinvention.

[0023]FIG. 13 is a partial side view of an endoscope assembly withinflatable cuffs according to still yet another embodiment of theinvention.

[0024]FIG. 14 is a partial side view of an endoscope assembly withinflatable cuffs according to still yet another embodiment of theinvention.

[0025]FIG. 15 is an end elevational view of the endoscope assembly ofFIG. 1 with the inflatable cuff in the inflated position.

DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention is generally directed to inflatable membersattached to an endoscope. Many of the specific details of certainembodiments of the invention are set forth in the following descriptionand in FIGS. 1 through 15 to provide a thorough understanding of suchembodiments. One skilled in the art will understand, however, that thepresent invention may have additional embodiments, or that the presentinvention may be practiced without several of the details described inthe following description.

[0027] In the drawings, like reference numbers identify similar elementsor steps. Further, it is understood that the inflatable members depictedin FIGS. 1 through 14 may assume a variety of sizes and shapes thatdepend on the amount of internal pressurization and/or the internalshape of a body cavity. Accordingly, for clarity of illustration, and toproperly illustrate internal features of the various embodimentsillustrated in FIGS. 1 through 14, the embodiments are shown at agenerally intermediate stage of inflation.

[0028]FIG. 1 is a partial cross sectional view of an endoscope assembly10 that includes a sheath 103 having an inflatable cuff 100 inaccordance with an embodiment of the invention. In this embodiment, theinflatable cuff 100 is circumferentially disposed about a body portionof the sheath 103, the body portion being sized to at least partiallyencapsulate an insertion tube 101 of an endoscope of the type shown, forexample, in FIG. 11.

[0029] When inflated, the cuff 100 may be symmetrically orasymmetrically disposed about the insertion tube 101. For example, FIG.15 is an end elevational view of the endoscope assembly 10 with theinflatable cuff 100 shown in an inflated position 105. As shown in FIG.15, in this embodiment, the inflatable cuff 100 is symmetricallycircumferentially disposed about the insertion tube 101. In alternateembodiments, the inflatable cuff 100 may assume any desired shape,including, for example, an eccentrically-disposed circular shape 107(FIG. 15) that is not symmetrically disposed about the insertion tube101, or a non-circular, asymmetric shape 109 (FIG. 15), or any othersuitable shape.

[0030] The insertion tube 101 can have a variety of cross sectionshapes, such as circular, semicircular, etc., and is fabricated from aresilient material so that an insertion tube wall 102 may be flexed. Theinsertion tube 101 also has an internal space 104 that is structured topermit the illumination of tissue in internal passages, and to convey animage of the illuminated area from the distal end 110 of the endoscopeto an external viewing device (not shown).

[0031] With reference still to FIG. 1, the endoscope sheath 103 has atransparent viewing window 118 located at the distal end 110 of thedisposable sheath 103 to allow the image to be conveyed to the externalviewing device. The window 118 may also be comprised of a lens capableof focusing an image on an image sensing device. The sheath 103 also hasa plurality of internal lumens to accomplish specific tasks. Forexample, a lumen 124 may be provided to direct a flow of rinse waterover the viewing window 118 in order to rinse vision-impairing matterfrom the window 118. A lumen 122 that is open at the distal end 110 maybe used to capture a biopsy sample taken from the surrounding tissuearea by means of an elongated forceps, or brush (not shown).Alternatively, the lumen 122 may be used to transfer a solution into abody passage during a lavage procedure. Further, the lumen 122 may alsobe used to transfer a compressed gas into a body passage in order todistend the passage for better optical viewing or biopsy sampling. Anadditional lumen 120 that is in fluid communication with a pressurizedfluid source (not shown) is used to inflate an inflatable endoscope cuff100, which will be described in greater detail below. The internallumens 120, 122 and 124 are comprised of a resilient material tomaintain flexibility of the sheath 103. The sheath 103 is covered with aflexible, resilient cover material 130 such as latex, polyvinylchloride,or polyurethane. Alternatively, other equally suitable materials for thecover material 130 are KRATON®, available from the GLS Corporation ofMcHenry, Ill., and C-FLEX®, available from Consolidated PolymerTechnologies, Inc. of Largo, Fla.

[0032] Still referring to FIG. 1, the inflatable endoscope cuff 100 iscomprised of a circular member positioned on the outer surface of thesheath 103. Although only a single inflatable cuff 100 is shown forclarity of illustration, it is understood that a plurality of cuffs 100may be positioned along the length of the endoscope assembly 10, andthat the plurality of cuffs 100 may be positioned at varying relativedistances. The inflatable cuff 100 may be located at any location alongthe working length of the endoscope assembly 10, and forms a closedannular space 136 that is capable of inflation by a pressurized fluid.An opening 134 projects through the cover material 130 and through thewall of the lumen 120 to permit the pressurized fluid retained withinthe lumen 120 to enter the inflatable cuff 100. To retain the cuff 100on the surface of the sheath 103, and to retain the pressurized fluidwithin the annular space 136, the cuff 100 is sealably fastened to thesurface of the sheath 103 at the cuff edges 138 with a suitable adhesiveplaced between the cuff edge 138 and the cover material 130. An exampleof a suitable adhesive is cyanoacrylate, although other equivalentadhesives exist. Alternatively, the cuff edges 138 may be joined to thecover material 130 either by thermally fusing the cuff edges 138 to thecover material 130, or by wrapping lengths of a retaining cord 131, suchas a surgical-type thread or other suitable material, over the cuff edge138 and securely tying the ends to sealably fasten the cuff edges 138 tothe cover material 130, although other methods for attaching the cuffedges 138 to the cover material 130 may also be used.

[0033] The inflatable cuff 100 may be formed from latex, KRATON®, orC-FLEX®, although other suitable flexible and resilient materials may beused. For example, soft polyurethane may also be used. Preferably, theinflatable cuff 100 is formed from a flexible and resilient materialwith a thickness that ranges between 0.003 and 0.010 inches, with adurometer value of between approximately 30 and approximately 50.Alternatively, the cuff 100 may also be formed from a relativelyinelastic material, so that it exhibits a relatively baggy shape whennot inflated.

[0034] With reference now to FIG. 2, a partial cross sectional view ofthe endoscope assembly 10 with an alternative embodiment of aninflatable endoscope cuff 200 is shown. As shown therein, the inflatableendoscope cuff 200 is comprised of a resilient toroidally-shaped member202 with an internal radius r and an external radius R. An opening 134projects through the cover material 130 and through the wall of thelumen 140 to permit a pressurized fluid retained within the lumeninterior space 112 to enter the inflatable member 202 through an opening210 in the interior diameter of the member 202. To sealably retain thepressurized fluid within the annular space 136, the toroidally-shapedmember 202 is sealably fastened to the surface of the sheath 103 at alocation that is closely proximate to the opening 134. Moreover, topositionally retain the member 202 in the desired location on thesurface of the sheath 103, it is preferable to join the interiordiameter of the member 202 to the cover material 130 along acircumferential contact area 220 to ensure that the member 202 maintainsits position on the endoscope assembly 10.

[0035]FIG. 3 shows a partial cross sectional view of the endoscopeassembly 10 with still another alternative embodiment of an inflatableendoscope cuff 300. As shown in FIG. 3, the inflatable endoscope cuff300 is comprised of a resilient circular member 302 positioned on theouter surface of the sheath 103. In this embodiment, the length of theendoscope cuff 300 is sufficient to allow the formation of a pair ofinflatable annular lobes 310 and 320 by attaching the circular member302 to the cover material 130 at an approximate midpoint location 350 ofthe cuff 300. The development of an inflatable endoscope member withdual lobes is regarded as particularly advantageous since the dual lobesare regarded as more effective in conforming to irregular internalsurfaces in body passages.

[0036] Still referring to FIG. 3, the cuff 300 may be retained at themidpoint location 350, and may be adhesively or thermally bonded to thecover material 130. Alternatively, the cuff may be attached to the covermaterial 130 at the mid point location 350 by a length of thread 131 (asshown in FIG. 1) wrapped around the cuff 300 that is securely knotted,although other methods may also be used. To retain the pressurized fluidwithin the inflatable annular lobes 310 and 320, cuff edges 340 aresealably joined to the cover material 130 using an adhesive or thermalbonding method as previously described. Openings 134 a and 134 b projectthrough the cover material 130 and through the lumen wall 140 to permitthe pressurized fluid retained in the lumen interior space 112 to enterthe lobes 310 and 320 during inflation.

[0037] Turning now to FIG. 4, a partial cross sectional view of theendoscope assembly 10 with yet another alternative embodiment of aninflatable endoscope member 400 is shown. The endoscope assembly 10according to this embodiment advantageously allows an inflatable memberto be formed on the disposable sheath 103 without placing a separatecircumferential member on the disposable sheath 103. The inflatablemember 400 is formed by providing an excess length of the cover material130 on the sheath 103 that may be drawn along the surface of the sheath103 by an edge fold 440 that extends circumferentially around the sheath103 to form a reentrant fold 450 in the cover material 130 that alsoextends circumferentially around the disposable sheath 103. The edgefold 440 is subsequently sealably attached to the cover material 130 ata surface location 460 to form a closed annular space 410 that iscapable of being inflated. The sealable attachment between the edge fold440 and the cover material 130 may be comprised of an adhesive orthermal bond. Alternatively, the attachment may be comprised of a lengthof retaining cord 131 (e.g. surgical-type thread, as shown in FIG. 1)that is wrapped over the edge fold 440 and securely knotted, althoughother methods may also be used. An opening 420 projects through thecover material 130 and is aligned with the opening 134 through the wallof the lumen 140 to permit the pressurized fluid retained within thelumen interior space 112 to enter the inflatable annular member 400during inflation. The member 400 may be sealably fastened to the surfaceof the sheath 103 at a location 412 that is closely proximate to theopening 134 to ensure that the lumen opening 134 in the lumen wall 140remains in substantial alignment with the opening 420 through the covermaterial 130.

[0038]FIG. 5 shows a partial cross sectional view of the endoscopeassembly 10 with still another alternative embodiment of an inflatableendoscope member 500. As in the previous embodiment, the inflatableendoscope member 500 is advantageously formed from an excess length ofthe cover material 130 that is disposed on the sheath 103. As shown inFIG. 5, the excess length of the cover material 130 is drawn in a firstdirection along the surface of the sheath 103 to form a first reentrantfold 530 with a first edge fold 570. The first edge fold 570 ispositioned approximately adjacent to the lumen opening 134. A secondreentrant fold 540 is then formed in the cover material 130 by drawingthe excess length in a second direction that is opposite to the first,to form a second edge fold 580 that is also positioned approximatelyadjacent to the lumen opening 134. When positioned approximatelyadjacent to the opening, the first edge fold 570 and the second edgefold 580 form an opening 590 into the inflatable enclosed annular space510. The first and second reentrant folds 530 and 540 are sealablyattached to the lumen wall 140 at locations 550 and 560, respectively,to ensure that the lumen opening 134 remains in substantial alignmentwith the opening 590. Adhesive or thermal bonding may form the sealableattachment at locations 550 and 560. As an alternative, a retaining cord131 (e.g. surgical-type thread, as shown in FIG. 1) may be inserted intothe first reentrant fold 530 through the opening 520 and also insertedinto the second reentrant fold 540 through the opening 525, both lengthsof retaining cord being wrapped around the circumference of thedisposable sheath 103 and securely knotted to retain the inflatablemember 500 in position on the sheath 103, although other methods mayalso be used.

[0039] Turning now to FIG. 6, a partial cross sectional view of theendoscope assembly 10 with still another alternative embodiment of aninflatable endoscope member 600 is shown. The inflatable endoscopemember 600 is similarly advantageously formed from an excess length ofthe cover material 130 that is disposed on the sheath 103. Drawing theexcess length of cover material 130 along the surface of the sheath 103in a first direction to form a first reentrant fold 660 with a firstedge fold 670 forms the inflatable member 600. The first edge fold 670is then positioned approximately adjacent to the opening 134 a. Drawingthe excess length in a second direction that is opposite to the firstdirection then forms a second reentrant fold 665 with a second edge fold675. The second edge fold 675 is similarly positioned approximatelyadjacent to the opening 134 b. The inflatable member 600 is divided intoa pair of inflatable lobes 610 and 620 by attaching the cover materialcomprising the member 600 to the lumen wall 140 at an approximatemidpoint location 680. The inflatable lobes 610 and 620 are inflatedwhen pressurized fluid retained within the lumen interior space 112enters the lobes through openings 134 a and 134 b. The first and secondreentrant folds 660 and 665 are sealably attached to the lumen wall 140at locations 672 and 674 to ensure that the lumen openings 134 a and 134b remain in substantial alignment with the lobe entrances 661 and 662.As previously described, adhesive or thermal bonding may be used to formthe sealable attachment at locations 672, 674 and 680. As analternative, a retaining cord 131 may be used to retain the position ofthe inflatable member on the sheath 103, although other methods may alsobe used.

[0040]FIG. 7 is a cross-sectional view of an endoscope assembly 20 inaccordance with yet another alternative embodiment of the invention. Theassembly 20 is comprised of a pair of flexible, resilient inflatablecuffs 100 a and 100 b that are positioned on an outer surface of adisposable sheath 130. The cuffs 100 a and 100 b are spaced apart alongthe length of the endoscope assembly 20 to define an inter-cuff length750. The sheath 130 encloses an interior space 705, and may bepositioned on an insertion tube 22 of an endoscope 21 of the type shown,for example, in FIG. 11.

[0041] Referring now to FIG. 11, an endoscope assembly 1000 according toan embodiment of the invention is shown. The endoscope assembly 1000includes an endoscope 21 having an elongated insertion tube 22 that iscomprised of a resilient material so that the tube may be flexed as itis positioned within an internal body passage 730. The insertion tube 22may be rigid, partially flexible or entirely flexible. The insertiontube 22 includes a distal portion 1002 that may be inserted into a bodycavity of a patient (not shown) and a working end 1004. The endoscope 21includes a headpiece 1006 that remains external to the patient during anendoscopic procedure. In the embodiment shown in FIG. 11, the headpiece1006 includes an eyepiece 1008 for viewing the scene through a viewinglens 1011 at the working end 1004 of the insertion tube 22, a pair ofbending control knobs 1012 for manipulating the position of the distalportion 1002 of the insertion tube 22, and a pair of fluid controlactuators 1014 for controlling the flow of fluids through tubes 1016 to(or from) the working end 1002. Endoscopes 21 of the type generallyshown in FIG. 11 are described more fully, for example, in U.S. Pat. No.5,931,833 to Silverstein, U.S. Pat. No. 5,483,951 to Frassica andAilinger, and U.S. Pat. No. 4,714,075 to Krauter and Vivenzio, whichpatents are incorporated herein by reference.

[0042] Referring now to FIGS. 7 and 11, the sheath 130 shows a pair ofinflatable cuffs 100 a and 100 b. It is understood, however, that thesheath 130 may include a plurality of inflatable cuffs located along thelength of the sheath 130, and that the inflatable cuffs may bepositioned along the length of the sheath 130 at varying inter-cufflengths 750. Further, the inflatable cuffs positioned along the lengthof the sheath 130 may be comprised of any of the inflatable cuffspreviously shown in FIGS. 2 through 6. Moreover, any combination of theinflatable cuffs previously shown in FIGS. 2 through 6 may be positionedalong the length of the sheath 130.

[0043] Referring again to FIG. 7, inflation lumens 702 and 704 arepositioned within the interior space 705 of the endoscope 20. Theinflation lumens 702 and 704 are fluidly connected to a source of aninflation fluid (not shown) at lumen ends 740 and 742. The lumens 702and 704 fluidly communicate through openings 134 a and 134 b to allowthe inflation fluid to be separately and selectively introduced into theannular spaces 136 a and 136 b. In alternate embodiments, the pair oflumens 702 and 704 may be replaced with a single lumen to provideinflation fluid to more than a single inflatable cuff on the endoscopeassembly 20, so that the cuffs may be simultaneously inflated. Inflationof the cuffs 100 a and 100 b through the inflation lumens 702 and 704thus allows an isolated body space 720 to be formed within theinter-cuff length 750 by sealably impressing the cuffs 100 a and 100 bagainst the body passage walls 732 of the body passage 730, as shown,for example, in the lower portion of FIG. 7.

[0044] Lumens 706 and 708 may optionally be provided within the interiorspace 705 that communicate through openings 722 and 724 into theinter-cuff length 750. The lumens 706 and 708 may be fluidly connectedto a variety of fluid or suction sources at the opposing ends 744 and746 in order to accomplish a variety of diagnostic tasks. For example,the lumen 706 may be fluidly connected to a source of a solution (notshown) to introduce the solution into the isolated body space 720. Thesolution may then be subsequently withdrawn from the space 720 throughanother lumen 708 for analysis. Alternatively, the lumen 706 may befluidly connected to a source of pressurized fluid (not shown) that maybe used to distend the isolated body space 720 prior to the introductionof a solution into the space 720 by the lumen 708. Although a pair oflumens 706 and 708 is shown in FIG. 7, it is understood that a singlelumen, or more than two may optionally be used.

[0045] The endoscope assembly 20 advantageously allows the cuffs 100 aand 100 b to be separately and selectively inflated to permit theendoscope assembly 20 to sealably adjust to variations in thickness andelasticity of the body passage wall 732. The endoscope assembly 20further advantageously allows a portion of the body passage 730 to befluidly isolated from the remaining portion of the passage so thatlavage, or any of the diagnostic procedures previously described, may beconducted in the isolated body space 720.

[0046]FIG. 8 is a cross-sectional view of an endoscope assembly 30 inaccordance with still another alternative embodiment of the invention.The assembly 30 includes an inflatable first cuff 800 a and a spacedapart inflatable second cuff 800 b, which are positioned on an outersurface of a disposable sheath 130. The cuff 800 a has a non-uniformwall thickness, and includes a forward portion 801 a, and a rear portion802 a that has a wall thickness that is less than the wall thickness ofthe forward portion 801 a. The cuff 800 b similarly has a non-uniformwall thickness, and also includes a forward portion 801 b, and a rearportion 802 b that has a wall thickness that is less than the wallthickness of the forward portion 801 b. The sheath 130 encloses aninterior space 705, and may be positioned on an insertion tube (notshown) that is comprised of a resilient material so that the tube may beflexed as it is positioned within an internal body passage 730.Alternatively, the insertion tube may be rigid.

[0047] Inflation lumens 702 and 704 may be positioned within theinterior space 705, and may be fluidly connected to a source of aninflation fluid (not shown) at lumen ends 740 and 742. The lumens 702and 704 communicate through the sheath 130 at openings 134 a and 134 bto allow the inflation fluid to separately and selectively inflate thefirst cuff 800 a and the second cuff 800 b. Alternatively, a singlelumen 707 (shown in FIG. 8 as a dotted line) may be used to provideinflation fluid to the first cuff 800 a and the second cuff 800 b sothat the cuffs may be simultaneously inflated.

[0048] In operation, inflation of the first cuff 800 a and the secondcuff 800 b through the inflation lumens 702 and 704 allows the cuffs 800a and 800 b to be impressed against body passage wall 732 of a bodypassage 730. Further, the non-uniform wall thicknesses of the first cuff800 a and the second cuff 800 b permit greater expansion of the rearportions 802 a and 802 b of the cuffs 800 a and 800 b than is obtainedin the respective front portions 801 a and 801 b of the cuffs 800 a and800 b when the cuffs 800 a and 800 b are inflated. The respective rearportions 802 a and 802 b of cuffs 800 a and 800 b thus develop alongitudinally-directed biasing force that acts in a direction 810 whenthe inflated rear portions 802 a and 802 b contact the body passage wall732. In alternate embodiments, the thicknesses of the front and rearportions 801 and 802 can be reversed so that the biasing force acts inan opposite direction.

[0049] Referring now to FIG. 9, a cross-sectional view of the endoscopeassembly 30 is shown with the first cuff 800a at least partiallyinflated, with the rear portion 802 a of the cuff 800 a contacting aportion of the body passage wall 732. In response to the biasing forcedeveloped by the rear portion 802 a , the assembly 30 is urged along thepassage 730 in the direction 810 from a first position 910 to a secondposition 920.

[0050]FIG. 10 is a cross sectional view of the assembly 30 with thefirst cuff 800 a in a deflated condition, and the second cuff 800 b atleast partially inflated. The rear portion 802 b of the cuff 800 bcontacts a portion of the body passage wall 732 and develops a biasingforce that further urges the assembly 30 along the passage 730 in thedirection 810 from the second position 920 to a third position 1010. Thesecond cuff 800 b may then be deflated, and the process repeated. Byalternately inflating and deflating the cuffs 800 a and 800 b in themanner described, the assembly 30 is able to incrementally move alongthe length of the body passage 730. Alternatively, for certain bodypassages 730 and for certain endoscopic procedures, it may be desirableto keep one of the cuffs 800 a or 800 b inflated at all times (e.g. toprovide an anchor), and to successively inflate and deflate the other ofthe cuffs to provide the desired longitudinal movement. It may also bedesirable to keep one of the cuffs 800 a or 800 b deflated (or toeliminate one of the cuffs 800 a or 800 b ) and to employ a single cuffto provide the desired longitudinal movement in the manner described.

[0051] Although the foregoing discussion has described the sequentialalternating inflation and deflation of the first cuff 800 a and thesecond cuff 800 b , in another embodiment, the cuffs 800 a and 800 b maybe simultaneously inflated and deflated using the single lumen 707 tomove the assembly 30 along the body passage 730. Further, although theendoscope assembly 30 as depicted in FIGS. 8 through 10 has a pair ofcuffs 800 a and 800 b , it is understood that the assembly 30 may becomprised of a plurality of inflatable cuffs located along the length ofthe assembly 30, and that the inflatable cuffs may be positioned alongthe length of the assembly 30 at varying distances. In addition, aportion of the plurality of cuffs may be oriented on the assembly 30 toapply a biasing force that urges the assembly 30 in a first direction toextend the assembly 30 into the body passage 730, while another portionof the plurality of cuffs are oriented on the assembly 30 to apply abiasing force in an opposing second direction to assist in the removalof the assembly 30 from the passage 730, as will be discussed in greaterdetail below, in connection with another embodiment.

[0052] It should also be understood that, although the foregoingembodiment discloses cuffs 800 a and 800 b having a variable wallthickness, other means may be used to obtain the differential expansionof the cuffs 800 a and 800 b in the manner described. For example, thecomposition of the material comprising the cuffs 800 a and 800 b may beformulated to provide the rear portions 802 a and 802 b with greaterelasticity, so that greater expansion occurs in these portions, asopposed to the front portions 801 a and 801 b . Still further, internalstructures, such as elastic cords 803 (FIG. 9) or elastic webs 805 (FIG.10), for example, or other suitable structures, may be incorporated intothe cuffs 800 a and 800 b that restrain the expansion of the frontportions 801 a and 801 b , while permitting the corresponding rearportions 802 a and 802 b to freely expand.

[0053] The foregoing embodiment advantageously allows an endoscopeassembly to develop a longitudinally-directed biasing force that permitsthe endoscope assembly to be positioned relatively deeply into a bodypassage, and further permits small, incremental movements of theendoscope assembly when properly positioned within the body passage. Theforegoing embodiment further allows the endoscope assembly to beconveniently dislodged in situations where the assembly may becomelodged in the passage.

[0054] As further shown in FIG. 9, in yet another embodiment, theassembly 30 may include one or more sleeve members 807 that partiallyinhibit the expansion of one or more of the cuffs 800 a, 800 b. In theembodiment shown in FIG. 9, the sleeve member 807 is attached to theouter surface of the sheath 130 and partially covers the first cuff 800a. As the first cuff 800 a is inflated, the sleeve member 807 allows therear portion 802 a of the first cuff 800 a to expand, and at leastpartially inhibits the expansion of the forward portion 802 b. Thesleeve member 807 may inhibit the expansion of the forward portion 802 bby any means, including by being relatively less elastic than the firstcuff 800 a, or may simply add additional thickness to the forwardportion 802 b. Thus, the differential expansion of the cuffs 800 a, 800b may be achieved, and the longitudinally-directed biasing force may becreated, in an inexpensive manner by adding one or more sleeve members807 to the assembly to achieve the beneficial results described above.

[0055]FIG. 12 is a partial side view of an endoscope assembly 1100according to still yet another embodiment of the invention. The assembly1100 includes an inflatable first cuff 1110 a and a spaced apartinflatable second cuff 1110 b that are positioned on the outer surfaceof the sheath 130. The first cuff 1110 a and the second cuff 1110 b maybe separately inflated, as described earlier in connection with otherembodiments. As in the embodiment shown in FIGS. 8 through 10, the firstcuff 1110 a has a non-uniform wall thickness, which includes a forwardportion 1111 a, and a rear portion 1112 a that has a wall thickness thatis less than the wall thickness of the forward portion 1111 a. The cuff1110 b also has a non-uniform wall thickness, including a forwardportion 1112 b and a rear portion 1111 b. The forward portion 1112 b hasa wall thickness that is less than the wall thickness of the rearportion 1111 b. The non-uniform wall thicknesses of the first cuff 1110a and the second cuff 1110 b permit greater expansion of the portions1112 a and 1112 b of the cuffs 1110 a and 1110 b than is obtained in theportions 1111 a and 1111 b of the cuffs 1110 a and 1110 b when the cuffs1110 a and 1110 b are inflated. The portions 1112 a and 1112 b thusdevelop a longitudinally-directed biasing force when the inflatedportions 1112 a and 1112 b contact the body passage wall 732.

[0056] Turning now to FIG. 13, a partial side view of the assembly 1100is shown with the first cuff 1110 a at least partially inflated. Therear portion 1112 a of the cuff 1110 a contacts the passage wall 732 andurges the assembly 1100 along the body passage 730 in a direction 1210.The cuff 1110 a may be periodically inflated and deflated to move theassembly 1100 along the passage 730.

[0057] Referring now to FIG. 14, a partial side view of the assembly1100 is shown with the second cuff 1110 b at least partially inflated.The front portion 1112 b of the cuff 1110 b contacts the passage wall732 and urges the assembly 1100 along the body passage 730 in adirection 1220 that is opposite to the direction 1210 shown in FIG. 13.

[0058] The foregoing embodiment advantageously permits the assembly 1100to be moved along the passage 730 in a direction that positions theassembly 1100 further into the passage 730, and also permits theassembly 1100 to be moved in the opposite direction, which may bebeneficial in preventing the assembly 1100 from being lodged in thepassage 730, in addition to further assisting an operator to preciselyposition the assembly 1100 within the passage 730.

[0059] The above description of illustrated embodiments of the inventionis not intended to be exhaustive or to limit the invention to theprecise form disclosed. While specific embodiments of, and examples of,the invention are described in the foregoing for illustrative purposes,various equivalent modifications are possible within the scope of theinvention, as those skilled in the relevant art will recognize.Moreover, the various embodiments described above can be combined toprovide further embodiments. For example, the various embodiments of theinflatable endoscope cuffs as previously described may be advantageouslypositioned along the length of the endoscope at uniform or varyingdistances to provide a plurality of inflatable cuffs along the length ofthe sheath. Further, different embodiments of the inflatable endoscopecuffs as previously described may be positioned at uniform or varyingdistances along the length of an endoscope to provide a plurality ofdifferent cuffs along the sheath to provide still further advantages.For example, the inflatable cuffs may be comprised of differentmaterials or material thicknesses to obtain different inflation ratesfor the inflatable cuffs and/or different cuff volumes when theinflatable cuffs are inflated by the fluid passage. Accordingly, theinvention is not limited by the disclosure, but instead the scope of theinvention is to be determined entirely by the following claims.

1. An endoscope assembly adapted to be inserted into an internal bodypassage, comprising: an elongated insertion tube; a sheath positionedover the insertion tube; at least two radially expandable flexiblemembers that sealably attach to the sheath to form at least two enclosedspaces capable of inflation, the flexible members being spaced apartalong a length of the sheath and defining one or more isolated bodyspaces that extend between the members when the members are inflatedwithin the body passage; and at least one first fluid passage thatfluidly communicates with the spaces.
 2. The endoscope assemblyaccording to claim 1 wherein the radially expandable flexible memberscomprise circumferential members, and wherein the enclosed spacescomprise annular enclosed spaces.
 3. The endoscope assembly according toclaim 1 wherein the radially expandable flexible members comprisecircumferential members that, when inflated, are symmetrically disposedabout the insertion tube.
 4. The endoscope assembly according to claim 1wherein the radially expandable flexible members comprisecircumferential members that, when inflated, are asymmetrically disposedabout the insertion tube.
 5. The endoscope assembly according to claim 1wherein the first fluid passage is adapted to be coupled to a source ofpressurized fluid.
 6. The endoscope assembly according to claim 1wherein the at least two flexible members comprise a resilient material.7. The endoscope assembly according to claim 1 wherein the at least onefirst fluid passage comprises a lumen coupled to at least one opening inthe sheath, the lumen being coupleable to a source of pressurized fluid.8. The endoscope assembly according to claim 1, further comprising atleast one second fluid passage that fluidly communicates with the one ormore isolated body spaces.
 9. The endoscope assembly according to claim5 wherein the at least one second fluid passage comprises a lumenextending from an opening in the sheath, the lumen being coupleable to asource of a fluid solution.
 10. The endoscope assembly according toclaim 5 wherein the at least one second fluid passage comprises a lumenextending from an opening in the flexible sheath to a suction source.11. The endoscope assembly according to claim 1 wherein the at least onefirst fluid passage comprises a first lumen extending from a firstopening in the sheath that communicates with a first annular space, anda second lumen that extends from a second opening that communicates witha second annular space.
 12. The endoscope assembly according to claim 1wherein at least one of the flexible members includes a reentrant foldin the sheath to form a flap with a base adjoining the insertion tubeand an edge disposed away from the base.
 13. The endoscope assemblyaccording to claim 1 wherein at least one of the flexible membersincludes a first reentrant fold in the sheath to form a first edge and asecond reentrant fold in the sheath to form a second edge, the first andsecond edges substantially abutting the opening.
 14. The endoscopeassembly according to claim 1 wherein the opening in the sheathcomprises a plurality of openings and wherein the flexible membercomprises a first reentrant fold in the sheath to form a firstcircumferential edge and a second reentrant fold in the sheath to form asecond circumferential edge, the first and second edges sealablyattached to the sheath proximate to the openings, the flexible memberbeing further sealably attached to the sheath at a position intermediatebetween the first and second circumferential edges.
 15. The endoscopeassembly according to claim 1 wherein the flexible members comprise anannular ring of a flexible material positioned over the opening andhaving an inner face and an outer face, the inner face beingsubstantially in facial contact with the sheath when not inflated, andthe outer face being disposed away from the sheath and having first andsecond peripheral edges which are sealably attached to the sheath. 16.The endoscope assembly according to claim 1 wherein the flexible membercomprises a toroidally-shaped member with an inner circumference and anouter circumference, the inner circumference being in facial contactwith the sheath, and the outer circumference being disposed away fromthe sheath, the inner circumference having an opening positioned overthe opening in the sheath and being sealably attached to the sheath atthe inner circumference.
 17. The endoscope assembly according to claim 1wherein the opening in the sheath comprises a plurality of openings andwherein the flexible member comprises an annular ring of a flexiblematerial with an inner face and an outer face, the inner face beingsubstantially in facial contact with the sheath when not inflated, andthe outer face being disposed away from the sheath and having first andsecond peripheral edges which are sealably attached to the sheath, theinner face being further sealably attached to the sheath at a positionintermediate between the first and second peripheral edges.
 18. Theendoscope assembly according to claim 1 wherein the flexible memberscomprise an elastomeric material.
 19. The endoscope assembly accordingto claim 1 wherein the flexible members comprise an elastomer with adurometer value of between approximately 30 and
 50. 20. The endoscopeassembly according to claim 1 wherein the flexible members comprise amaterial with a thickness of approximately about 0.003 inches toapproximately about 0.010 inches.
 21. The endoscope assembly accordingto claim 1 wherein the flexible members are sealably attached to theflexible sheath with an adhesive.
 22. The endoscope assembly accordingto claim 1 wherein the flexible members are sealably attached to theflexible sheath by thermal fusion.
 23. The endoscope assembly accordingto claim 1 wherein the flexible members are sealably attached to theflexible sheath with a retaining cord.
 24. The endoscope assemblyaccording to claim 1 wherein at least one of the flexible membersincludes a non-uniform wall thickness.
 25. The endoscope assemblyaccording to claim 1 wherein at least one of the flexible membersincludes a first portion having a first wall thickness and a secondportion having a second wall thickness, the first thickness beingdifferent from the second thickness.
 26. The endoscope assemblyaccording to claim 1 wherein at least one of the flexible membersincludes a first portion having a first elasticity and a second portionhaving a second elasticity, the first elasticity being different thanthe second elasticity.
 27. The endoscope assembly according to claim 1wherein at least one of the flexible members includes an internalstructure disposed within the associated body space and attached to afirst portion of the flexible member that partially inhibits expansionof the first portion.
 28. The endoscope assembly according to claim 1,further comprising a sleeve member attached to an outer surface of thesheath and engaged with a first portion of at least one of the flexiblemembers, the sleeve member partially inhibiting an expansion of thefirst portion.
 29. A sheath having a body portion adapted to at leastpartially encapsulate an insertion tube of an endoscope, comprising: atleast two radially expandable flexible members sealably attached to thebody portion to form at least two enclosed spaces capable of inflation,each space having at least one first opening that projects through thebody portion, and wherein the flexible members are spaced apart along alength of the body portion to define one or more isolated body spacesthat extend between the members when the members are inflated within thebody passage.
 30. The sheath according to claim 29 wherein at least oneof the radially expandable flexible members comprises a circumferentialmember, and wherein at least one of the enclosed spaces comprises anannular enclosed space.
 31. The sheath according to claim 29 wherein atleast one of the radially expandable flexible members comprises acircumferential member that, when inflated, is symmetrically disposedabout the insertion tube.
 32. The sheath according to claim 29 whereinat least one of the radially expandable flexible members comprises acircumferential member that, when inflated, is asymmetrically disposedabout the insertion tube.
 33. The sheath according to claim 29 whereinat least one of the flexible members includes an internal structuredisposed within the corresponding enclosed space and attached to a firstportion of the at least one flexible member that partially inhibitsexpansion of the first portion.
 34. The sheath according to claim 29,further comprising a sleeve member attached to an outer surface of thebody portion and engaged with a first portion of at least one of theflexible members, the sleeve member partially inhibiting an expansion ofthe first portion.
 35. The sheath according to claim 29 wherein the atleast one first opening is adapted to be coupled to a source ofpressurized fluid.
 36. The sheath according to claim 29 wherein the atleast two flexible members comprise a resilient material.
 37. The sheathaccording to claim 29 wherein the at least one first opening furthercomprises a lumen coupled to the at least one first opening, the lumenbeing coupleable to a source of pressurized fluid.
 38. The sheathaccording to claim 29, further comprising at least one second opening inthe body portion that fluidly communicates with the one or more isolatedbody spaces.
 39. The sheath according to claim 38 wherein the at leastone second opening comprises a lumen extending from the second opening,the lumen being coupleable to a source of a fluid solution.
 40. Thesheath according to claim 38 wherein the at least one second openingcomprises a lumen extending from the second opening, the lumen beingcoupleable to a suction source.
 41. A method of forming an endoscopeassembly, comprising: providing a sheath; providing a first fluidpassage that extends through the sheath to define a first opening in thesheath; forming a first flexible member about the sheath and defining afirst space in fluid communication with the first opening, the firstspace being adapted to be inflated; providing a second fluid passagethat extends through the sheath to define a second opening in thesheath; and forming a second flexible member about the sheath anddefining a second space in fluid communication with the second opening,the second space being adapted to be inflated, the second inflatablemember being spaced apart from the first inflatable member along thetube to define an isolated body space therebetween.
 42. The methodaccording to claim 41 wherein forming a first flexible member comprisesforming a first circumferential member, and wherein the first spacecomprises a first annular space.
 43. The method according to claim 41wherein forming a first flexible member comprises forming a firstcircumferential member that, when inflated, is symmetrically disposedabout the sheath.
 44. The method according to claim 41 wherein forming afirst flexible member comprises forming a first circumferential memberthat, when inflated, is asymmetrically disposed about the sheath. 45.The method according to claim 41 wherein forming a first flexible membercomprises forming a first flexible member that includes an internalstructure disposed within the corresponding enclosed space and attachedto a first portion of the first flexible member that partially inhibitsexpansion of the first portion.
 46. The method according to claim 41wherein providing a sheath comprises providing a sheath including asleeve member attached to an outer surface thereof, the sleeve memberbeing engaged with a first portion of at least one of the first andsecond flexible members, the sleeve member partially inhibiting anexpansion of the first portion.
 47. The method according to claim 41wherein providing a first fluid passage comprises forming a lumenextending from the first opening in the sheath to a source ofpressurized fluid.
 48. The method according to claim 41 whereinproviding a second fluid passage comprises forming a lumen extendingfrom the second opening in the flexible sheath to a source ofpressurized fluid.
 49. The method according to claim 41, furthercomprising providing a third fluid passage that extends through thesheath to define a third opening that fluidly communicates with theisolated body space.
 50. The method according to claim 49 whereinproviding a third fluid passage further comprises forming a lumenextending from the third opening in the sheath to a source ofpressurized fluid.
 51. The method according to claim 49 whereinproviding a third fluid passage comprises forming a lumen extending fromthe third opening in the sheath to a suction source.
 52. The methodaccording to claim 41, further comprising: providing a fourth fluidpassage that extends through the sheath to define a fourth opening inthe sheath; and forming a third flexible member in fluid communicationwith the fourth opening in the sheath to define an enclosed third spaceadapted to be inflated, the third inflatable member being spaced apartfrom the second inflatable member along the tube to define a secondisolated body space that extends between the second and the thirdmembers.
 53. The method according to claim 52, further comprising:providing a fifth fluid passage that extends through the sheath todefine a fifth opening that fluidly communicates with the secondisolated body space.
 54. The method according to claim 52 whereinproviding a fifth fluid passage comprises forming a lumen extending fromthe fifth opening in the sheath to a source of pressurized fluid. 55.The method according to claim 52 wherein providing a fifth fluid passagecomprises forming a lumen extending from the fifth opening in the sheathto a suction source.
 56. The method according to claim 41 whereinforming a first flexible member includes forming a first flexible memberhaving a non-uniform wall thickness.
 57. The method according to claim56 wherein forming a second flexible member includes forming a secondflexible member having a non-uniform wall thickness.
 58. The methodaccording to claim 41 wherein forming a first flexible member includesforming a first flexible member having a first portion with a first wallthickness and a second portion with a second wall thickness, the firstwall thickness being different from the second wall thickness.
 59. Themethod according to claim 58 wherein forming a second flexible memberincludes forming a second flexible member having a first portion with afirst wall thickness and a second portion with a second wall thickness,the first wall thickness being different from the second wall thickness.60. The method according to claim 41 wherein forming a first flexiblemember includes forming a first flexible member having a first portionwith a first elasticity and a second portion with a second elasticity,the first elasticity being different from the second elasticity.
 61. Themethod according to claim 60 wherein forming a second flexible memberincludes forming a second flexible member having a first portion with afirst elasticity and a second portion with a second elasticity, thefirst elasticity being different from the second elasticity.
 62. Amethod of using an endoscope assembly within an internal passage,comprising: positioning a sheath having at least two spaced apart andradially expandable members at least partially over an insertion tube ofan endoscope; at least partially inserting the insertion tube and sheathinto the internal passage; and inflating the radially expandable membersto form at least one isolated body space therebetween.
 63. The methodaccording to claim 62, further comprising directing a fluid into the atleast one isolated body space from a fluid source.
 64. The methodaccording to claim 63, further comprising directing a fluid into the atleast one isolated body space from a pressurized fluid source to distendthe space.
 65. The method according to claim 62, further comprisingapplying suction to the at least one isolated body space from a suctionsource to remove a fluid from the space.
 66. An endoscope assembly forinsertion into an internal body passage, comprising: an elongatedinsertion tube; a sheath at least partially encapsulating the insertiontube; at least one radially expandable flexible member sealably coupledto the sheath and adapted to be inflated against the internal bodypassage and to exert a force along a longitudinal axis of the insertiontube when inflated against the internal body passage; and at least onefluid passage coupleable to a source of pressurized fluid that fluidlycommunicates with the at least one member.
 67. The endoscope assemblyaccording to claim 66 wherein the at least one radially expandableflexible member comprises a circumferential member.
 68. The endoscopeassembly according to claim 66 wherein the at least one radiallyexpandable flexible member comprises a circumferential member that, wheninflated, is symmetrically disposed about the insertion tube.
 69. Theendoscope assembly according to claim 66 wherein the at least oneradially expandable flexible member comprises a circumferential memberthat, when inflated, is asymmetrically disposed about the insertiontube.
 70. The endoscope assembly according to claim 66 wherein the atleast one flexible member includes an internal structure disposed withina corresponding enclosed space and attached to a first portion of the atleast one flexible member that partially inhibits expansion of the firstportion.
 71. The endoscope assembly according to claim 66 wherein thesheath includes a sleeve member attached to an outer surface of thesheath and engaged with a first portion of the flexible member, thesleeve member partially inhibiting an expansion of the first portion.72. The endoscope assembly according to claim 66 wherein the at leastone fluid passage comprises a lumen extending from an opening in thesheath to the source of pressurized fluid.
 73. The endoscope assemblyaccording to claim 66 wherein the at least one radially expandableflexible member includes a first portion capable of a first expansionwhen inflated, and a second portion capable of a second expansion wheninflated, the first expansion being greater than the second.
 74. Theendoscope assembly according to claim 73 wherein the first portioncomprises a first material, and the second portion comprises a secondmaterial.
 75. The endoscope assembly according to claim 73 wherein thefirst portion has a first elasticity, and the second portion has asecond elasticity, the first elasticity being greater than the secondelasticity.
 76. The endoscope assembly according to claim 73 wherein thefirst portion has a first elasticity, and the second portion has asecond elasticity, the first elasticity being greater than the secondelasticity.
 77. The endoscope assembly according to claim 73 wherein thefirst portion has a first cross sectional thickness, and the secondportion has a second cross sectional thickness, the first crosssectional thickness being different from the second cross sectionalthickness.
 78. A sheath having a body portion adapted to at leastpartially encapsulate an insertion tube of an endoscope, the insertiontube being insertable into an internal body passage, comprising: atleast one radially expandable flexible member sealably coupled to thebody portion and adapted to be inflated against the internal bodypassage and to exert a force along a longitudinal axis of the insertiontube when inflated against the internal body passage, and wherein thebody portion includes at least one opening that projects through thebody portion and is coupleable to a source of pressurized fluid thatfluidly communicates with the at least one member.
 79. The sheathaccording to claim 78 wherein the at least one radially expandableflexible member comprises a circumferential member.
 80. The sheathaccording to claim 78 wherein the at least one radially expandableflexible member comprises a circumferential member that, when inflated,is symmetrically disposed about the insertion tube.
 81. The sheathaccording to claim 78 wherein the at least one radially expandableflexible member comprises a circumferential member that, when inflated,is asymmetrically disposed about the insertion tube.
 82. The sheathaccording to claim 78 wherein the at least one opening comprises a lumenextending from the opening in the body portion to the source ofpressurized fluid.
 83. The sheath according to claim 78 wherein the atleast one radially expandable flexible member includes a first portioncapable of a first expansion when inflated, and a second portion capableof a second expansion when inflated, the first expansion being greaterthan the second.
 84. The sheath according to claim 83 wherein the firstportion comprises a first material, and the second portion comprises asecond material.
 85. The sheath according to claim 84 wherein the firstmaterial has a first elasticity, and the second material has a secondelasticity, the first elasticity being greater than the secondelasticity.
 86. The sheath according to claim 78 wherein the firstportion has a first elasticity, and the second portion has a secondelasticity, the first elasticity being greater than the secondelasticity.
 87. The sheath according to claim 78 wherein the firstportion has a first thickness, and the second portion has a secondthickness, the first thickness being different from the secondthickness.
 88. A method of using an endoscope assembly within aninternal passage, comprising: positioning a sheath having at least oneradially expandable member over an insertion tube of an endoscope, theat least one radially expandable member being adapted to be inflatedagainst the internal body passage and to exert a force along alongitudinal axis of the insertion tube when inflated against theinternal body passage; at least partially inserting the insertion tubewith the sheath positioned thereon into the passage; and inflating theat least one member to move the insertion tube along the passage. 89.The method according to claim 88, further comprising deflating the atleast one member.
 90. The method according to claim 88 wherein inflatingthe at least one member to move the insertion tube includes moving theinsertion tube into the passage.
 91. The method according to claim 88wherein inflating the at least one member to move the insertion tubeincludes moving the insertion tube out of the passage.
 92. The methodaccording to claim 88 wherein positioning a sheath having at least oneradially expandable member over an insertion tube of an endoscope,comprises positioning a sheath having first and second radiallyexpandable members, and wherein inflating the at least one memberincludes inflating the first and second radially expandable members. 93.The method according to claim 92 wherein inflating the first and secondmembers includes simultaneously inflating the first and second membersto move the members in a first direction.
 94. The method according toclaim 92 wherein inflating the first and second members includessequentially inflating the first and second members to move the membersin a first direction.
 95. The method according to claim 92 whereininflating the first and second members includes inflating the firstmember to move in a first direction, and inflating the second member tomove in a second direction.
 96. The method according to claim 88 whereininflating the at least one radially expandable member comprisesinflating a circumferential member that, when inflated, is symmetricallydisposed about the insertion tube.
 97. The method according to claim 88wherein inflating the at least one radially expandable member comprisesinflating a circumferential member that, when inflated, isasymmetrically disposed about the insertion tube.
 98. The methodaccording to claim 88 wherein positioning a sheath having at least oneradially expandable member over an insertion tube of an endoscopecomprises positioning a sheath having a radially expandable member thatincludes a first portion capable of a first expansion when inflated, anda second portion capable of a second expansion when inflated, the firstexpansion being greater than the second expansion.